Originally posted by Mike Crowley i have a 80 lb pot on ely's 13 gage kantholl 10 inch's of insulation.
i melt eltromelt, cook for 8 hours at 2280 squeeze for 4 hours , no bubs or cords just nice glass. so far the 13 gage are on there 6th week the 14 gage i was using only lasted 3 weeks .

mike

how long do you get on a set of elements? what yield do you get (lbs batch vs. lbs glass)?

In an effort to reduce dust, and because I am close enough that shipping doesn't kill me, I switched from SP87 to Gaffer (Phillips).

In my huge, 60# Denver, I work down about 60 - 65% between charges. Charge in 2 or 3, +/- 10# - 12# fills. Set to 2250 and leave it 24 hrs. Down to 2140 to work.

Clear, bubble free.
.............................

The variable is the popcorn effect when the Gaffer goes in. The pellets pop and land on the sill. There they melt and create a seal to do the door.

I like the glass (I don't work fast enough yet for slow setting to be a problem.... to me it's a virtue) but may have to go back to SP87 to be able to open the door.
Jim V

>>>>>>>>>>>>>>>>>>>
I have been melting SP87 for 3 years now in my Denver 135 # furnace.

When I charge, I usually let the furnace sit at whatever the working temp. was until I put the last of the batch in to fill the crucible. Then I ramp up to 2225 and let it cook for 10 hours, drop the temp. to 1900, let it squeeze for 2 hours then ramp up to 2050 where I work at.

I almost every time come out with beautiful clear, bubble free glass.

I am going to try Gaffer in the fall and see what happens.
Ed Kozlowski
>>>>>>>>>>>>>>>>>>>>>

Yes for the most part 24/7 ( with a weekend
off here and there)in a production, make
a meager living off it environment.

I don't know what you are doing but I know that
my furnace design gets long life, I suspect due
to the fact that the elements are in a separate
chamber from the batch. Long element life is not all that
it's cracked up to be however. the last
few months of those elements it was taking forever
to melt as they lost power. the power loss is gradual
as they age and you don't notice it while
it's happening. you really notice it when you put
a new set in and are able to quit charging 3 hours
earlier than the last time. I think maybe I
will start looking for a surplus hourmeter to
put on my furnace to keep better track of the element life.
I hope to have the dicipline to
put new elements in next time before the old ones wear out
and quit. I charge 3 times a week and would rather
finish sooner than later.

I think that the Denver design
is so poor that it has created a concern
about "element life" that would not exist if you
never started marketing something as ill suited
to melting studio glass as their design is. I know
that some people have made it work by jumping thru
hoops but putting the elements behind the pot and
out of harms way just makes lots more sense.
No offence intended to those of you using Denvers
but I can't imagine wanting to hold at a melt temperature for 24 hours
just so you can melt a few degrees colder and try to coax a little extra
"life " out of the elements.
I already suffer in my production by not being able
to empty my pot after a days blowing and be able
to refill it quickly enough to begin blowing the
next morning. The wound elements won't put out enough power
in my design to melt, cook, fine, and
squeeze 70 - 100#'s of batch overnight. I've seen
gas fired units that pull that off with no trouble
but my furnace was cheap to build and I got what I payed for.

My oven has very low thermal mass but I regularly
finish blowing with 10-20 #'s of glass in the bottom
and pull the plug to go to a show. it cools at a rate far slower
than the 200 degrees per hour that I bring it back up. This is a small "perk" that I enjoy with
my furnace.http://www.kurtwalrath.com/largeglassstudio/furnace.htm

Sayyyyy, I just LOVE the new crown and door design (what was the inner ring casted out of again?).

The only worry I would have is that the inner crucible is air sealed from the furnace air chamber. I understand (from much firsthand experience) that with a small gap over the crucible there's the risk of glass pops getting on an element, but the problem I had when I tried to let the crown come down to meet the pot was that when charging it created too large of a temp differential from inside the pot to the outside of the pot and the pot pitted and went to hell 3x as fast as when I left 1" of air space between the top of the crucible and the crown. (My solution involved leaving the 1' gap and preheating my charge)

Are you fired up yet? Is this new and improved SuperKurtMelter running any more efficient than the last? Is a gathering port that's only 8" wide by 11" deep big enough?

Originally posted by kurt walrath I got 8 months out of my 1st set of 13 ga. elements. They are $20 each from Jen-Ken.

your heaters only cost $20? i pay a lot more than that for the kanthal apm elements i buy. could they actually be a kanthal nichrome heater? i think thumb was using nichrome for a while that someone told him were apm.

Originally posted by kurt walrath Yes for the most part 24/7 ( with a weekend
off here and there)in a production, make
a meager living off it environment.

I don't know what you are doing but I know that
my furnace design gets long life, I suspect due
to the fact that the elements are in a separate
chamber from the batch. Long element life is not all that
it's cracked up to be however. the last
few months of those elements it was taking forever
to melt as they lost power. the power loss is gradual
as they age and you don't notice it while
it's happening. you really notice it when you put
a new set in and are able to quit charging 3 hours
earlier than the last time. I think maybe I
will start looking for a surplus hourmeter to
put on my furnace to keep better track of the element life.
I hope to have the dicipline to
put new elements in next time before the old ones wear out
and quit. I charge 3 times a week and would rather
finish sooner than later.

You just need to find a way to fit an extra leg of elements in there. It's like going from a flat six to a V8, and the best part is it doesn't take any extra power to hold temp with the extra elements - and charging is WAY faster. (It also gives you the ability to keep temp after the first element goes down)

As far as element longevity goes, a set really only needs to last as long as the crucible. No sense having the pot crap out a month before the elements (unless you're in the replacement furnace biz - hmmmm).

As it says at the beginning of my furnace page
I used my spares as an extra leg after the 1st
few times I charged. The only way to get more
elements in there would be to rebuild it with
another layer of ifb in the chamber. I put 3
grooves per brick in there to begin with. If
I was to do it again I would probably make the
chamber taller so I could add more elements.
Time is money when charging and the element cost
in cheap in the long run in my situation.

Quote:

your heaters only cost $20?

They are a stock replacment item from Jen - Ken
Kilns. I'm pretty sure they are Kanthal A-1.
If they are nichrome then 8 months melting 100#
of batch 3 times a week is really good.

Quote:

The only worry I would have is that the inner crucible is air sealed from the furnace air chamber.

In real life I found that my frax seal between the crown and the pot burns out. there is a small ( 1/2")
gap between them after the frax goes. I dont think
that I get much stuff passing through the crack though.

Quote:

Are you fired up yet? Is this new and improved SuperKurtMelter running any more efficient than the last?

It's not really new and improved. i just swapped elements
a few months ago and while I was in there I rammed
some plastic castaBLE over the place where the
drips from the sill went down and contacted the
2900 deg castable of the crown. it couldn't take the
direct glass contact and it pitted the castable
and spit tiny stones into the glass. That rammable
stuff can handle the glass contact fine and my stone
problem disappeared.

I don't think it's any more efficient than before
it just melts way faster with new elements than
with 6-8month old elements. (more power)

Quote:

Is a gathering port that's only 8" wide by 11" deep big enough?

I pull some big gathers through it but I wish it
was 10" wide sometimes when I scrape the sides.

A 7-1/2" wide gather would probably make a 16"
goldenflow, it's alot of glass.

They are a stock replacment item from Jen - Ken
Kilns. I'm pretty sure they are Kanthal A-1.
If they are nichrome then 8 months melting 100#
of batch 3 times a week is really good.

That's what I thought for years untill Tom at Pine Ridge called Paragon for some specs to make a match for Mike down in UT (whom I eagerly await news of the new furnace from - he's using a stock ST100 crown). To my suprise I was running nichrome all this time , and still getting 6-8 months off of them. There's another ST100 going on 7 months and he has the nichrome wire.

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